Reinforcement for a pole



Aug. 9, w66 Vl. M. SPIER 3,265,401

REINFORCEMENT FOR A POLE FledvJan. 29, 1964 BY BLUM ,Moscow/'rz /75F16/zomaar, B1. UM KHPLA v ATTORN E YS United States Patent O 3,265,401REINFORCEMENT FOR A POLE I Martin Spier, 50 Park Ave., New York, NX.10016 Filed Jan. 29, 1964, Ser. No. 341,006 4 Claims. (Cl. 280-11.37)

This invention relates to improvements in a pole such as a ski pole.

One object of the invention is to provide an improved ski pole ofincreased strength and of increased resistance to denting, while stillof light weight. Another object of the invention is to increase therigidity and reduce the flexing of the pole under stress conditions ofuse.

Another object of the invention is to provide a ski pole, meeting t-heabove requirements, the component parts of which can be readilyfabricated and assembled.

In accordance with a preferred embodiment of the invention, I provide anelongated, hollow, thin walled shaft having a downwardly tapered fbore.I provide an axially extending insert within and intermediate the endsof the bore. This insert has at least three circumferentially spacedvanes, the outer edges of whichy correspond in taper with and abutfrictionally flush against the surface of the bore. Such insert, whichmay optionally consist of two interlocking plates shaped to cross atright angles and thereby provide four vanes, may be readily frictionallyassembled within the bore of the hollow shaft.

As one of the particular features of the invention, a filling materialis provided, in situ, to bond the vanes in place and to strengthen thepole. Specifically, in accordance with known techniques, materials arepoured into the hollow shaft which react in situ to form a materialsu-ch as foam polyurethane. This material extends the length of thepole, or at least to t-he upper level of the insert, land also extendsagainst the vanes. As a feature of the invention, the vanes haveapertures through which the lill extends bondingly so as to lix theinsert in position within the shaft.

Optionally, the ll may be provided in several pours, of differentdensity, for example, of greater density at the bottom, where the boreis of relative small diameter. of intermediate density in the zone ofthe insert, and of reduced density in the to-p of the pole.

The insert serves to rigidify the pole, and thereby to strengthen it andreduce its flexing. The foam ll serves to hold the vanes from twistingor turning, lixes the vanes axially within the pole and adds strength tothe aluminum skin of the pole. As a further feature, the foam lillprevents the aluminum skin of the pole from denting as readily as wouldbe otherwise possi-ble, and also reduces vibration of the pole.

Other objects and advantages of the invention will become apparent fromthe following description, in conjunction with the annexed drawing, inwhich preferred embodiments of the invention are disclosed.

In the drawing,

FIG. 1 is an elevational view of the improved ski pole, in accordancewith the invention, in vertical position.

FIG. 2 is a vertical section on line 2-2 of FIG. l, essentially showingthe zone in which the insert is located. FIG. 2 shows the condition ofthe assembly prior to the lill.

FIG. 3 is la section on line 3-3 of FIG. 2.

FIG. 4 is an enlarged fragmentary view, similar to FIG. 2, and showingthe assembly with the foam lill in position.

FIG. 5 is an exploded perspective view of the insert.

Upon reference to the drawing in detail, it will be noted that thedrawing shows a ski pole comprising hollow shaft 11, handle 12 for theupper end of shaft 11 and Hee snow engaging member 13 mounted on shaft11 adjacent its tip end.

Shaft 11 is essentially conventional, the invention residing in theelements inserted within the bore of shaft 11. Shaft 11 is made of lightmetal alloy or other known material for this purpose. Speciically, it ispreferable to use a light weight aluminum alloy sufficiently heattreatedand cold-worked to provide maximum strength. The material is drawn, inconventional manner, to provide the shaft 11 which is substantiallyuniformly downwardly tapered from its top to at least the generalvicinity of its lower end, as clearly shown in the drawing. Shaft 11 maybe approximately 54 inches in length, by way of example, and may have anoutside diameter of approximately three-quarters of an in-ch at itsupper end. The outside diameter of shaft 11 in the general vicinity ofits lower end may be approximately one-half inch. Within the limits ofpresently known drawing techniques, shaft 11 has a peripheral wall 11aof approximately uniform thickness throughout the length of shaft 11.Accordingly, the peripheral wall of the internal bore 11b of shaft 11 isalso downwardly tapered, corresponding to the outer surface of wall 11a.

The handle 12, which closes the upper end of bore 11b, may be of anysuitable type generally used on ski poles, and preferably includes awrist strap 12a. The snow engaging member 13 may be of any suitabletype, such as a basket ring, generally used on ski poles, and includes ahub 13a mounted upon shaft 11 slightly above the tip 14 of shaft 11, byany suitable means. Tip 14 may be of any suitable type generally used onski poles, and is inserted into the lower end of shaft 11, so as toclose the lower end of bore 11b, by any suitable means (not shown).

In accordance with the invention, insert 15 is placed within bore 11b.While a number of constructions are possible for insert 15, one simpleconstruction is shown -in the drawing. In this construction, insert 15comprises a pair of elongated plates 16 and 17 of the same overall shapeand dimensions. Plates 16 and 17 may be of any suitable material.Optionally, lthey are stamped from any suitable lightweight -but strongmetal. Alternatively, they may be molded from rigid plastic.

Plate 16 is elongated in the direction of the axis of the bore 11b andhas side edges 16a and 16b, bottom edge 16e and upper edge 16d. Plate 17correspondingly has side edges 17a and 17b, bottom edge 17c and upperedge 17d. The edges 16a and 16b are straight and downwardly convergent.Accordingly, plate 16 is downwardly tapered, the taper of plate 16 beingthe same as the taper of bore 11b, at least within the zone of shaft 11in which the insert is to be placed. Within this zone, the width ofplate 16 corresponds to the diameter of bore 11b, at each level of plate16, so as to insure a close frictional iit of plate 16 within bore 11b,with plate 16 extending diarnetrically .as well as axially, and with theplate edges 16a and 16b closely frictionally abutting the wall of bore11b. It will be understood that a corresponding discussion applies toplate 17.

The end edges 16a` and 16d of plate 16 extend transversely to the axisof shaft 11 in the inserted condition of plate 16. Of course,corresponding statements apply to plate edges 17c and 17d. vPlate 16 hasan axially extending slot 18 extending from edge 16d toward edge 16o,the lower end of slot 18 being substantially equidistant with respect tothe edges 16e and 16d. The width of slot 18 is substantially equal tothe `thickness of plates 16 and 17.

Plate 17 has a slot 19 corresponding to slot 18, except that slot 19extends from edge 17c upwardly to the midpoint of plate 17.

Plates 16 and 17 are assembled before insert 15 is placed in bore 11b.For this assembly, the plates are placed end to end and at right anglesto each other with the edges 17a` and 16d adjacent each other, and theplates are `then slid toward each other with plate 17 entering slot 18and with plate 16 at the same time entering slot 19. The plates are slidwithin the slots until edges 16d and 17d are on the same level, andedges 16e` and 17c are on the same level. In this position, ythe upperend of slot 19 and the lower end of slot 18 are in contact, with plate17 frictionally received within the entire length of slot 18 and withplate 16 frictionally received within the entire length of slot 19. Suchassembly of plates 16 and 17 of insert 15 thereby defines four vanes 20.These vanes 20 radiate outwardly from the central axis of insert 15,upon which slots 18 and 19 are located. Also, such vanes 20 arecircumferentially spaced ninety degrees apart. Furthermore, the outeredges of vanes 20 (the edges 16a, 16h, 17a and 17b respectively)correspond in taper wit-h the surface of bore 11b.

While other constructions of insert are possible, the disclosedconstruction is highly preferred since it makes it possi-ble tofalbricate insert 15 of extremely lightweightV material. l It ispossible to use such lightweight material in view of the provision ofthe foam plastic fill to be described below. If insert 15 were extrudedin a single piece, it would have to be substantially heavier and wouldrequire considerably greater expense of fabrication, than is the casewith the preferred construction. In any event, whatever t-heconstruction, there should be at least three vanes 19. Of course, in thepreferred construction, as indicated above, there are four such vanes.In yassembly of insert 15 with shaft 11, the insert 15 can be simplydropped into bore 11b, through the open upper end thereof, prior tomounting olf handle 12 on the upper end of shaft 11. Insert 15 then.d-rops until the edges of the vanes are in flush abutment with the wallof bore 11b. The precise axial location of insert f15 relative to shaft11 will depend upon the respective upper and lower diameters of insert15 and the length thereof.

As an important feature of the invention, the vanes are provided withapertures through which the foam plastic fill can pass, for bondingpurposes. The apertures also lighten the insert. Each platte 16 and 17has horizontal rows circular apertures 21, two per row, yas shown inFIG. 5. Accordingly, each vane 20 has a Vertical succession ofyaperture-s 21, one above the other, as best shown in FIG. 2, along theentire height of the vane. In addition, each vane 20 has verticallysuccessive notches 22 extending from its outer edge and locatedoutwardly of apertures 21. Vertically, notches 22 and apertures .21 mayalternate.

In the claims, unless otherwise specified, the term rapertures includesnotches 22 or apertures 21. Depending upon desired dimensions, eithernotches 22 alone, apertures 21 alone, or both may be used.

As a further importance feature of the invention, after the insert is inplace, and before the top of the pole is closed, a foam plastic fill 25is formed in situ within bore 11b, to the bottom thereof and extendingupwardly, optionally to lat least the upper end of the insert and evenbeyond that point as shown in FIG. 4.

By way of example, the known required chemicals for reaction in situ toproduce foam polyurethane may be dispensed intro bore 11b, within whichthey react to form the desired final composition. There may be one suchfill, or several partial lls, one on the other. In the case of severalpartial fills, they may be controlled, in known manner, to be ofdifferent densities, for example, of

greatest density at the bottom, least density at the top andintermediate den-sity 'in between.

It will be especially noted that the fill 2S extends through apertures21 `and notches 22, as shown in FIG. 4. Accordingly, the vanes arebonded to the fill and prevented fro=m shifting vertically or flexing.Accordingly, the insert with apertures, together with the ll, permitgreat improvement in pole quality with minimum addition in weight. Theyconstruction increases resistance of the pole to flexing or denting,and dampens Vibrations thereof.

While I have disclosed a preferred embodiment of `the invention, andhave indicated various changes, omissions and additions which maybelmlade therein, it will be apparent that various other changes,omissions and `additions may be made in the invention without departingfrom the scope and spirit thereof.

While polyurethane foam is the preferred foamed plastic, other plasticor plastic-like materials having similar properties when in la foamedstate can be utilized. Thus, foamed rubber latex is amenable toutilization in the present invention. In general, the foamed plastic is'formed in situ by adding the pl-astic and generating gases by theaddition of a suitable gas releasing agent while maintaining Ianelevated temperature. Alternatively, gas may be bubbled tinto thedesired area so as to form lthe foamed plastic therein. p

Optionally, after ,assembly of plates 16 and 17, their ends may -besecured together from moving, as by welding or swaging in the case ofmetal, or cement or chemical or other welding in the case of plastic.

I claim:

1. In a pole and the like, the combination of an elongated, hollow,4thin-walled shaft having a downwardly Itapered bore which has Ian axis,an axially extending rigid insert within said bore intermediate its endsand having at least three radially extending, circumferentially spacedvanes the outer edges of which correspond in taper with and aboutfrictionally flush against the surface of said bore, and an in situ foamplastic ll within said shaft and filling said bore from below to abovesaid insert, said vanes having apertures through which said fill extendsbondingly to x said insertin position within said shaft.

2. Combination .according to claim 1, said insert comprising two platesone having an `axial slot from its upper end to its midpoint and theother having 'an axial slot from its lower end to `its midpoint, saidplates interlocked to form four vanes with each plate frictionallyreceived within the full length of the slot of the plate.

3. Combination according to claim 2, said apertures extending to theouter edges of said vanes. p

4. Combination according to claim 2, said apertures being vertically'aligned and spaced in a single vertical row in each v'ane.

References Cited by the `Examiner 4/ 1944 Switzerland.

BENJAMIN HERSH, Prz'marry Examiner. MILTON L`. SMITH, Examiner.

1. IN A POLE AND THE LIKE, THE COMBINATION OF AN ELONGATES, HOLLOW,THIN-WALLED SHAFT HAVING A DOWNWARDLY TAPERED BORE WHICH HAS AN AXIS, ANAXIALLY EXTENDING RIGID INSERT WITHIN SAID BORE INTERMEDIATE ITS ENDSAND HAVING AT LEAST THREE RADIALLY EXTENDING, CIRCUMFERENTIALLY SPACEDVANES THE OUTER EDGES OF WHICH CORRESPOND IN TAPER WITH AND ABOUTFRICTIONALLY FLUSH AGAINST THE SURFACE OF SAID BORE, AND AN IN SITU FOAMPLASTIC FILL WITHIN SAID SHAFT AND FILLING SAID BORE FROM BELOW TO ABOVESAID INSERT,